At present, for producing of a liquid crystal display element device and the like, there is used a photolithography technique for transferring a fine pattern formed on a mask onto a photosensitive substrate. In the producing step using the photolithography technique, a mask is placed on a mask stage which moves two dimensionally, and a projection exposure apparatus is used in this photolithography technique. The projection exposure apparatus projects and exposes a pattern formed on the mask onto a photosensitive substrate to which sensitizer is applied. The sensitizer is placed on a substrate stage which two dimensionally moves through a projection optical system. The photosensitive substrate is a substrate in which sensitizer is applied to a surface of a glass plate or the like. As shown in FIG. 7, a conventional exposure apparatus is assembled by placing a pedestal (column) 106 on which a mask stage 104 and a projection optical system (not shown) are placed is placed on a pedestal (surface plate) 102 on which a substrate stage 100 is placed.